Monday, January 31, 2011

Just a bit about the nest excavation. 66 days ago a nest containing approximately 95 eggs was relocated to the hatchery because the nest was below the high-tide line. (If the nest isn't above the high-tide line, water will cover it, and the eggs won't receive either the oxygen from or the heat from the sun they need in order to hatch.) Two days ago (the day before we arrived), approximately 50-55 of those eggs hatched, and the hatchlings were then transported from the hatchery to the water. Two days more were given for the rest of the eggs to hatch; none did, so today we excavated the nest.

During the excavation, we removed the shells from the unhatched eggs as well as the shells from the hatched eggs and sorted them into three groupings: hatched eggs; unhatched eggs; and SAGs (Shelled Albumen Globule: 'extra', yolk-less eggs the turtles lay presumably to keep the air circulating among the 'real', yolk-filled eggs in the nest). We then transported all of the eggs close to the water and dug a deep hole next to the eggs. One of the biologists then counted both the SAGs and the hatched eggs and recorded that data in the log book. She put all of those shells into the hole. She then went to work on the unhatched eggs. Opening each of the unhatched shells, she looked at what was inside and grouped the eggs into four categories depending on how long into the growth process what she found inside was. Once that data was recorded, she placed all of those eggs into the hole and filled in the hole with sand -- she told us that the waves would eventually take these eggs out to sea.

We had quite a crowd around us as we worked through this process: lots of people who were spending time on the beach. I'm sure had I been one of thise beach people, I would have watched us, too -- it was a genuinely fascinating process to be part of.

I gather we may be relocating a nest tomorrow or the next day. Out tonight at 10:15, then back in six hours later. Time for a quick nap!

Because I was assigned to the early morning (5 a.m. to 7:30 a.m.) beach shift today (more about that below...), I wasn't on the roster to go out last night. But out I went -- for half the shift (9:10-midnight), and I'm awfully glad I did! My group, assigned to north Playa Grande beach, didn't spot any leatherbacks, but we did get to see olive ridley hatchlings making their way from the nest to the water -- so cool. I'm guessing there were about 80 or so hatchlings -- about 2.5 inches top to bottom, crawling their way across the sand and into the surf. Two members of our group measured the hatchilings -- height, width, and size of head -- and recorded their findings while the rest of us made sure predators kept their distance. About 20 minutes later, we saw a black turtle come ashore to lay her eggs, but, alas, she had other plans, so no luck there: she did a U-turn and headed back into the water!

Another group -- sweeping south Playa Grande beach -- did get to see a leatherback, but, like our black turtle, she executed what they call a false crawl: in; change of mind; back out. These false crawls aren't uncommon, and the chances are good that the same turtle will return either later that night or the next night to lay her eggs.

Night patrol goes out three hours before high tide and stays out for three hours after -- 6 hours total. When high tide occurs before, right around, or very shortly after midnight (as it did last night), two people are assigned to the morning walk shift to see if there was any activity after the night patrol finished its sweeps. I went out this morning with one of the biologists, and we found two little olive ridley hatchlings doing their darnedest to get to the water -- yep, they were stragglers from the same nest that produced the large batch the night before! The biologist and I picked up the two tiny things and helped them get to the water a bit more quickly than they might otherwise have arrived there. They were very cute, I must admit: the one I held (remember: all of 2-2.5 inches long) took the opportunity to use its front flippers to wipe the sand out of its eyes -- a total 'awwww' moment.

This afternoon the project manager will give us a presentation on the leatherbacks, and then at 3:00 we're going to the hatchery to participate in the excavation of a nest.

I have beach patrol tonight, and high tide is later than it was last night, so I will be out from approximately 10:00 p.m. until 4:00 a.m. It's a late high tide (as I think it will be for the rest of the week), so there will be no morning walk for anyone tomorrow.

Some more Turtle Fun Facts 4 U:

no one knows for sure what the life expectancy is for a leatherback, but they estimate it to be about 80 years

olive ridleys lay approximately 100 eggs each session, and close to 80% of those eggs will hatch -- that's a higher percentage of hatchlings than the leatherbacks enjoy

leatherbacks crawl using both front flippers simultaneously -- they more or less 'swim' through the sand; olive ridleys alternate their front flippers, so they crawl -- who knew?

Lower schoolers: thanks for the questions! I will make sure to ask them at this afternoon's session with the project manager. Look for the answers in a later post.

Sunday, January 30, 2011

Flew in this morning from San Jose -- 45 minutes in a twin-propeller puddle jumper. Kind of cool: the sky was clear, we were close enough to the ground, and I had a window seat, so there was much to see down below! As we approached the landing strip -- a gravel pathway, about 8-10 feet wide -- we flew out across the Pacific Ocean and then back in towards land. The person in charge of the turtle research program met the Earthwatch representatives and drove us here to the station. After a late breakfast at Keke's (an open-air restaurant connected to a hotel), we unpacked and then had our first briefing.

Each night, some of us will have beach duty (to find any turtles that have come ashore to lay eggs and then to take data on both the turtle and the egg-laying) and some of us will have hatchery duty (to protect them from water or predators, some of the nests are moved to the hatchery, and those of us on hatchery duty get to watch the eggs -- you guessed it! -- hatch). Both beach and hatchery duties last six hours and are scheduled around high tide, so, for tonight, they take place from 9:10 p.m. until 3:10 a.m.; morning beach patrol runs 5-7 a.m. I'll know more about all three once I've been assigned to each -- I think tonight I get to go on part of the beach duty, and then I have beach patrol tomorrow morning.

A few pieces of information I've picked up, some of which I'm betting some of you already know:

leatherback turtles have been around since the dinosaurs

a female leatherback will lay eggs every 3-4 years

she will lay approximately 65 eggs each time she comes on shore

she will come on shore anywhere from 7-10 times each laying season, and she will do so every 9-10 days

the laying season here runs from October to March

she will then return to the Galapagos and environs until it's time for her to lay agai

Time to go have our headlights covered with red cellophane (no white lights near the turtles -- and, therefore, no pictures of them) and then head down to the hatrchery.

Friday, January 28, 2011

Now that I've nailed down everything at school and done my rehearsal packing to make sure I'll have what I need and that it all fits in my duffle, I'm finally getting excited to head down to Costa Rica and meet the people I'll be working with for the next week. I fly out of Newark tomorrow (Saturday) mid-afternoon, spend the night in San Jose (more or less in the middle of the country), and then head west Sunday morning via plane to Tamarindo, the airport closest to the expedition site. I gather it's quite warm and sunny these days in Costa Rica (and not the rainy season, as it was this past August when I was there), and, as much as I love the winter and the snow, I have to say, it will be nice to hang out in shorts and t-shirts for a few days. Senora Epstein gave me a little farewell travel kit, so I'm now all stocked up on sunscreen, lip balm, antibacterial Wet Ones, and Clorox wipes (to which she affixed a note: "Not for your body!!!" -- she takes such very good care of me, and I'm a better person for it). I'll get my dog, Jake, down to my sister's tomorrow, and then it's off to airport at noon.

A big thanks to everyone at Collegiate who pitched in to make this trip possible for me. I hope I do all of you and the school proud!